1. Field of the Invention
The present invention relates to a data storage medium support member, a chucking device, a brushless motor, and a disc drive apparatus.
2. Description of the Related Art
A disc drive apparatus, such as an optical disc drive, has a brushless motor which rotates a disc. The brushless motor has a chucking device which rotates together with a rotor unit. The disc drive apparatus drives the brushless motor while holding the disc with the chucking device and a clamper provided above the chucking device, thereby rotating the disc.
The brushless motor as described above has a turntable which supports the disc while making contact with an inner edge of the disc. A brushless motor equipped with such a turntable is disclosed in JP-A 2004-110919, for example.
Some of such turntables have, within its raised guide/positioning portion for guiding the disc, a recessed accommodating portion for accommodating an attraction device, such as an annular permanent magnet. In the case where such turntables are produced by resin injection molding, a trace of a channel over which molten resin flows at the time of the injection molding and the aforementioned recessed accommodating portion must be formed in each single turntable.
Of all portions of the turntable, a portion where the trace of the molten resin channel is formed, in particular, needs to have a sufficient thickness to prevent deformation at the time of mold release. Inclusion of the trace of the molten resin channel and the recessed accommodating portion accordingly leads to an increased axial dimension of the turntable, making it difficult to reduce the thickness of the turntable.